The present invention relates to a rolling mill for milling cereals or similar material and including a housing and a plurality of pairs of rolls exchangeably arranged in the housing.
In the usual construction of such rolling mills, the pairs of rolls of the mills are mounted in a cast housing or in a housing welded together from sheet material, whereby the bearings for the rolls are received individually in the housing and fixed to the latter. Thereby the housing has not only to take-up the forces resulting from the weight of the rolls and the drive means therefor, but also the forces resulting from the milling process per se, which in turn will result in heavy expensive machines. If, in such a construction, one of the rolls of a pair of rolls has to be exchanged, due to wear or a defect in one of the rolls or in a roll pair, it is necessary to dismantle all bearings, resulting in a cumbersome and time-consuming operation and requiring a plurality of operators for carrying out such an exchange.
In order to simplify an exchange of the rolls and to carry out such an exchange in a shorter time, rolling mill housings are known in the art which are split in the region of the roll bearings so that, after removal of one housing part, the bearings of all rolls are easily accessible and so that the rolls together with the bearings may be removed from the housing. Such constructions are, for instance, shown in the German Pat. Nos. 671,248 and 840,790. While in these constructions any necessary exchange of the rolls is simplified, these constructions require expensive housings, so that the aforementioned constructions have not been accepted by the trade.
A construction for rolling mills is further known in which the housing, formed from welded steel sheets, is provided with circular openings in two opposite walls thereof, through which the rolls of a roll pair are inserted. Compact drive heads, which include the bearings for the roll pair as well as parts of the drive for rotating the latter, are placed into the circular openings and releasably connected by screws to the housing. In order to remove the roll pair, the two drive heads are disconnected from the housing and the rolls pulled in axial direction through the aforementioned opening out of the housing. Such a construction is, for instance, shown in the German Pat. No. 440,927.
Rolling mills are further known in the art in which the rolls thereof are supported in a usual manner at one end in separate bearings mounted on one side wall of the housing, and in which the other end of each roll is mounted in a bearing which is received in a cover plate connected to the opposite side wall of the housing, and in which the cover plate closes an opening in the other side wall which corresponds to the diameter of the respective roll, so that the roll, after removing of the cover plate, may be moved in axial direction into or removed from the housing. Such a construction is, for instance, disclosed in the German Pat. No. 926,383.
Common to all these known rolling mills is that the housing as well as the roll set or sets have to be individually constructed for the respective purpose and must be correspondingly harmonized with each other. Such a necessary individual construction is evidently detrimental as far as an economical manufacturing or quick repairs are concerned.